def send(self, envelope):
        try:
            # Attempt to send
            self._send_envelope(envelope)
            # Reset retry delay on success
            self.retry_delay = 1.0
            self.error_logged = False
        except ConnectionError as e:
            # Exponential backoff
            if not self.error_logged:
                logger.error(f"Spotlight server unreachable at {self.url}: {e}")
                self.error_logged = True

            # Wait before retry
            time.sleep(self.retry_delay)
            self.retry_delay = min(self.retry_delay * 2, self.max_retry_delay)

            # Retry once, then give up for this envelope
            try:
                self._send_envelope(envelope)
                self.retry_delay = 1.0
            except ConnectionError:
                # Silently drop envelope after retry
                pass

    def capture_envelope(self, envelope):
        # type: (Envelope) -> None

        # Check if we're in backoff period - skip sending to avoid blocking
        if self._last_error_time > 0:
            time_since_error = time.time() - self._last_error_time
            if time_since_error < self._retry_delay:
                # Still in backoff period, skip this envelope
                return

        body = io.BytesIO()
        envelope.serialize_into(body)
        try:
            req = self.http.request(
                url=self.url,
                body=body.getvalue(),
                method="POST",
                headers={
                    "Content-Type": "application/x-sentry-envelope",
                },
            )
            req.close()
            # Success - reset backoff state
            self._retry_delay = self.INITIAL_RETRY_DELAY
            self._last_error_time = 0.0
        except Exception as e:
            self._last_error_time = time.time()

            # Increase backoff delay exponentially first, so logged value matches actual wait
            self._retry_delay = min(self._retry_delay * 2, self.MAX_RETRY_DELAY)

            # Log error once per backoff cycle (we skip sends during backoff, so only one failure per cycle)
            sentry_logger.warning(
                "Failed to send envelope to Spotlight at %s: %s. "
                "Will retry after %.1f seconds.",
                self.url,
                e,
                self._retry_delay,
            )